This invention relates generally to gas turbine engines and, more particularly, to an improvement in diffusers for gas turbine engines having axial flow compressors and annular combustors.
In gas turbine engines of the type having axial flow compressors and annular combustors, it is desirable that compressor discharge flow be divided between a radially inner plenum, a radially outer plenum, and a combustor dome feed chamber at the combustor dome generally in the proportions assumed during engine design. Achievement of such distribution is complicated, however, by the radially variable nature of the compressor discharge flow field during engine operation, this variability manifesting itself as a variation in compressor discharge pressure and/or compressor discharge flow radially across the compressor discharge opening. In one proposal for achieving proportional compressor discharge distribution, a diffuser between the compressor discharge opening and the combustor divides the discharge flow between inner and outer plenums and a combustor dome feed chamber ahead of the combustor dome, the diffuser cooperating with the combustor in defining a fixed slot for bleeding air from the combustor dome feed chamber to the inner plenum to automatically compensate for discharge profile irregularities. For a detailed description of this proposal reference may be made to U.S. Pat. No. 3,877,221, issued Apr. 15, 1975 to Arthur H. Lefebvre et al and assigned to the assignee of this invention. A gas turbine engine having a diffuser according to this invention incorporates novel improvements over the Lefebvre et al proposal and other heretofore known structures.